ULN2803A / Ic vs Vsat

ACGUY

Guru 11170 points

Other Parts Discussed in Thread: ULN2003V12

Hi,

Our customers have plan to change from competitor darlington to TI darlington.

I want to know the Vce(sat) when Ic<10mA.

However, I can't read out it from Figure 1 and 2 in datasheet.

Could you provide the information me?

Regards,

Nagai

over 9 years ago

0 Michael J Schultis over 9 years ago

TI__Mastermind 25115 points

Hello Nagai-san,

From the Figures, it looks like on the order of 0.6 to 0.7V. Do you need more precise data? This will take till the end of the week to acquire as I will have to re-run this test on the bench.

Best,
Michael

0 Ron Michallick over 9 years ago in reply to Michael J Schultis

TI__Guru**** 171346 points

Nagai-san,

Also expect about a -2mV/C temperature coefficient for the low current VOUT.

0 ACGUY over 9 years ago in reply to Ron Michallick

Guru 11170 points

Hello Michael-san , Ronald-san ,

Thank you for your reply.
Our customer want to know the information about Vce(sat) in Ic=0.5mA to 3mA.
If you could, we want to know tolerance of Vce(sat), min and max.

Regards,
Nagai

0 Ron Michallick over 9 years ago in reply to ACGUY

TI__Guru**** 171346 points

Nagai-san,

Minimum is 0.25V and maximum 0.88V based on a few evaluations I have done.
( I added 50mV guard band and included -40C to 125C temperature)

Why does it matter?

0 ACGUY over 9 years ago in reply to Ron Michallick

Guru 11170 points

Ronald-san,

Thank you for answer.

>> Why does it matter?
Our customer is planning a LED control using the device.
LED's Vf, Ic and Vce(sat) are important information for design.

By the way, I posted anather question in this forum.
e2e.ti.com/.../523301

Could you answer it?

Best regards,
Nagai

0 Ron Michallick over 9 years ago in reply to ACGUY

TI__Guru**** 171346 points

Nagai-san,

How many channels are needed; what is the LED supply voltage?
For low current and low VOL, ULN2003V12 is a good choice, but it is 7 channel device.

0 ACGUY over 9 years ago in reply to Ron Michallick

Guru 11170 points

Ronald-san,

Currently, Our customer uses competitor's 8-channels device.
ULN2803A is pin compatible to it.

LED supply voltage is unknown.
Supply voltage and current limiting resistance are will be determined in a few days.

Regards,
Nagai

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ULN2803A / Ic vs Vsat